1. Field of the Invention
Process and device for dispensing pressure-sensitive adhesive laminate sections from a movable primary onto a movable secondary carrier band.
2. Description of the Related Art
The invention relates to a process for dispensing pressure-sensitive adhesive laminates or laminate sections from a movable primary to a movable secondary carrier band, said laminates, upon deflection of the primary band around a dispenser edge, being detached and dispensed onto the secondary band.
It is known how to produce and use pressure-sensitive adhesive laminate sections which are adhesive over a surface. These may be, for example, labels, stickers, transdermal therapeutic systems (TTSs) or double-sided adhesive tape. The pressure-sensitive adhesive surface or a pressure sensitive adhesive-rendered matrix of these laminate sections is typically covered by a carrier band at least partially projecting beyond the same. Technically, these laminate sections are fabricated by punching a matrix and a backing layer, which is connected thereto, down to the carrier web by means of an appropriate tool, and peeling off and discarding a projecting lattice of matrix and a backing layer.
With this kind of fabrication of dermal or transdermal therapeutic, pressure-sensitive adhesive laminate sections, the surface coating of the carrier band may become damaged upon punching through the matrix and a backing layer connected with the matrix, which in the case of prolonged storage will cause problems in releasing the matrix from the carrier layer, especially where the therapeutic system possesses a strong tendency for cold flow, enabling the matrix to unintentionally form a pressure-sensitive adhesive bond with the carrier layer, which carrier layer has not been rendered adhesive.
This problem can, however, be avoided by transferring the transdermal plasters, following the separation of the sections of the laminate by punching them out of an original laminate, to a final, secondary carrier layer. A corresponding process is described in WO 97/22315. This process has as a prerequisite that a transdermal therapeutic system which is to be transferred can be released from a primary carrier band when being guided around a dispenser edge, and can thus be transferred to the final, secondary carrier band. If, however, the adhesive force of the matrix exceeds a certain value, this method can no longer be applied as the pressure-sensitive adhesive matrix in this case is no longer detachable from the carrier band but is deflected along with the primary carrier band.
In known dispensing methods, such as described, for instance, in WO 97/22315, the primary carrier band, with the segregated laminate sections, e.g. plasters, is guided in the direction of conveyance over a dispensing edge, the plaster in the process being peeled from the carrier band along the entire width of the plaster. The peeling process here takes place in the direction of the band. If the adhesion of the plaster to the primary carrier layer is very strong, this may, even in the case of a very acute dispensing angle, cause the plaster to be pulled around the edge along with the primary carrier layer without becoming detached therefrom, thus making a dispensing process impossible.